Thermostatic valve for steam trap



May 22, 1956 E. L. MYERS THERMosTATIc VALVE FOR STEAM TRAP Filed Feb. 2,1953 United States Patent() 2,746,685 p 'HIERMOSTATIC VALVE FOR STEAMTRAP Errol L. Myers, Detroit, Mich., assignor to Howard O. Trerice,Detroit, Mich.

Application February 2, 1953, Serial No. 334,461 3 Claims. (Cl. 236-53)My invention relates-to steam traps and more particularly to a valvestructure therefor comprising a thermal responsive valve applicable toan upright bucket type trap, and actuable to automatically operate thetrap mechanism when air pockets happen to collect in the trap interiorto such an extent as to prevent normal trap operation.

While applicants assignees have for several years installed .valves ofthis` type in bucket type traps, the valve assemblies have been such asto make it practically impossible to. make repairs or replace suchvalves in the field. These valves have in generalv been permanentlymounted internally of the bucket, and it has been necessary to returnthe entire bucket to the factory when replacement of the thermostatvalve element becomes necessary.

It is an object of my present invention to facilitate assembly of thesethermally responsive valves and to facilitate servicing of same byconstructing the assembly with a replaceable thermostat valve elementwhich can be quickly detachably assembled with an adapter mounted on anexternal surface of the bucket.

A further object of the invention is to provide for maximum life with aminimum of service expense by constructing an improved valve assemblyincorporating an adapter operable in conjunction with a snap actionthermostat valve to provide a free unrestricted opening whereby amaximum of rapid flow of the trapped water is had to minimize collectionand build up sludge formations about the opening and the valve seat,that will in time interfere with the normal eicient operation of thetrap.

For a more detailed understanding of my invention,

reference may be had to the accompanying drawing illustrating apreferred embodiment of the invention, in which like characters refer tolike parts throughout the several views, and in which: h Fig. l is avertical sectional View of a steam trap hav- 111g an upright bucket andcarrying a thermally responsive snap action valve assembly constructedin accordance with the present invention.

Fig. 2 is a fragmentary side elevational view of the bucket showing saidthermally responsive valve in elevation.

Fig. 3 is a detailed sectional view of the valve assembly taken on theline 3-3 of Fig. 2 and showing the valve closed, and

Fig. 4 is a detailed sectional view of the valve assembly similar toFig. 3, but showing the valve open.

The steam trap A, with which my invention is applied, comprises a steamtrap body consisting of a casting providing a chamber or sump 11 inwhich a condensed moisture from the steam line will collect. Thiscondensate will buoyantly support the upright bucket 12, said bucketcarrying the valve 13 which is guided in suitable guides 14 and seatedto close the outlet' 15. This outlet 15 is carried by the head casting16 secured to the body 10 and this head casting provides a closure2,746,685 Patented May 22, 1956 for the open end casting 10 and isprovided with an outlet 17. Steam is admitted to the trap through theinlet 18.

In the normal operation of the trap, the water collected in the chamberor sump 11 will rise and eventually overflow into the bucket 12, causingthe bucket to sink, opening outlet 15 and the water is discharged fromthe bucket and when the amount Withdrawn is suflicient to buoyantlysupport the bucket, it closes off outlet port or opening 15.

At times an air pocket may form in the trap and when this occurs, itdoes not allow for the entrance of steam` into the trap and the confinedair pocket becomes great enough to block the rise of water in the trap,preventing this water from overflowing the rim of the bucket, thuspreventing normal trap operation.

A snap valve 20 is embodied in the wall of the bucket near the bottom,and when air pocket is trapped in the trap as described above, nomoisture from the steam is added thus resulting in the temperature ofthe water dropping. When the temperature of the water in sump 11 islowered to a predetermined low degree, the thermal responsive valve 20is actuated to open the bucket interior to the water in sump 11, theintroduction of such Water overcoming the buoyancy of the bucket andopening the outlet 15.

The thermal valve structure 2t! is mounted externally of the bucket..This valve structure assembly comprises an adapter 21, preferablycircular in plan and the adapter and bucket are provided with a numberof holes, the adapter being located by these holes and secured to theexternal surface of the wall of the bucket by hollow tubular rivets 22,said hollow rivets providing a plurality of open passages 23 connectingthe bucket interior with the space or chamber 24 defined in said adapterwithin the annular peripheral flanged lip 25 of the adapter. The adapteris constructed with a central hub 26 having a tapped hole 27 at thecenter, the lip being concentric with this hub.-

A shouldered screw 2S is threaded into the tapped hole 27 and clamps thebi-metal thermostat disc 29 to the at outer face of the hub, theperipheral portion of this disc overlying the lip 2S or" the adapter.

Under normal operation of the steam trap, the temperature of the waterin the sump il is such as to maintain the disc valve 29 seated in thelip .'25 closing of the interior of the bucket from the sump l1, asillustrated by Fig. 3, but as the temperature of the water in the sumpfalls to a predetermined degree, the bi-metal disc 29 will snap to anopen position as illustrated in Fig. 4. The Water then suddenly andrapidly rushes past the lip 2S into space 24 through passage 23 into thebucket. After the discharge of the bucket and the entrapped air pocket,the trap again operates normally and the disc 29 is subjected to hotsteam and water and it snaps shut. Then snap action and sudden openingand closing of the opening about the periphery of the adapter providesfor a rapid flow of water and minimizes the build up or accumulation ofsludge deposits about the periphery of the lip or the valve seat.

The bi-metal disc 29 is readily removed to replace a new one whennecessary, this being necessary from an orifice, said valve structurecomprising an adapter provided with a perforated plate portion and anannular flange encircling said plate portion to form an outwardlyopening recess, a plurality of hollow rivets in said plate perforationsfor securing said adapter to the wall of said steam trap bucket andacting to conduct water i'low, and a snap acting thermostatic disccarried by said adapter and located to overlay the annular flange toclose ot communication between the outside and inside of said bucket,said snap disc distortable in response to temperature changes to snapopen and provide a free unrestricted opening about the entire peripheryof said adapter.

2. A thermostatic snap valve structure assembled with a steam trapbucket for controlling water iloW through an orice, said valve structurecomprising an adapter provided with a perforated plate portion and anannular flange encircling said plate portion to form an outwardlyopening recess, said bucket having openings registering with theperforations in said adapter plate portion, a plurality of hollow rivetsthreaded in said plate perforations and openings in said bucket forsecuring said adapter to the wall of said steam trap bucket and actingto conduct water flow, a snap acting thermostatic disc concentricallydisposed relative to said adapter, and means disposed substantiallycentrally of said disc and adapter to secure said disc to the adapter,said thermostatic disc located to overlay the annular ange to close oftcommunication between the outside and inside of said bucket, said snapdisc distortable in response to temperature changes to snap open andprovide a free unrestricted opening about the entire periphery of saidadapter.

3. A thermostatic snap valve structure assembled with a steam trapbucket for controlling water ow through an orice, said valve structurecomprising an adapter provided with a perforated plate portion and anannular ilange encircling said plate portion to form an outwardlyopening recess, said bucket having openings registering with theperforations in said adapter plate portion, a plurality of hollow rivetsthreaded in said plate perforations and openings in said bucket forsecuring said adapter to the Wall of said steam trap bucket and actingto conduct water ow, a snap acting thermostatic disc concentricallydisposed relative to said adapter, said adapter having a centrallydisposed post and said perforations arranged around said post, a snapacting thermostatic disc concentrically disposed relative to saidadapter, and means disposed centrally of said disc to secure same to theadapter post, said thermostatic disc located to overlay the annularflange and said recess to close off communication between the outsideand inside of said bucket, said snap disc distortable in response totemperature changes to snap open and provide a free unrestricted openingabout the entire periphery of said adapter.

References Cited in the le of this patent UNITED STATES PATENTS1,420,045 Lippert I une 20, 1922 1,812,722 Spencer June 30, 19312,232,583 Zies Feb. 18, 1941 2,509,482 Crise May 30, 1950

